<p>The "thumbs up" is not something you can add. It is an integrated part of the Forum feature; which newer wikis don't have and older wikis will have removed starting mid-January.
</p><p>It isn't precise, but you could use
Status. It isn't precise because all it does is just check the timestamp of the user's last logged activity and then makes a guess based on that. However, it is better than nothing if you really want something like it.
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